Low-Cost and Recyclable Photocatalysts: Metal Oxide/Polymer Composites Applied in the Catalytic Breakdown of Dyes

Abstract

Novel metal oxide/polymer composite photocatalysts prepared by photocuring with common metal oxide particles (ZnO or CeO2) and acrylic ester monomers have been investigated for the first time. Metal oxide particles were fully integrated with the acrylate polymer network based on the crosslink of poly ethylene glycol diacrylate (noted below as Poly-PEG) by photopolymerization upon mild light source (LED@405 nm) irradiation. The prepared metal/oxide composite showed excellent performance in the photodegradation of Acid Black dye (used as a benchmark pollutant) in an aqueous environment. Indeed, under UV lamp irradiation for 60 min, the degradation of Acid Black reached 59% and 56%, in the presence of 10 wt% ZnO/Poly-PEG and 3 wt% CeO2/poly PEG, respectively. Markedly, the new reported photocatalysts have offered much better performance over the conventional TiO2 photocatalytic material used as a control (39% degradation using 1 wt% TiO2/poly PEG). In turn, the new proposed metal oxide/polymer composites were further characterized by a range of analytical characterization methods, including the swelling test, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), dynamic mechanical analysis (DMA), UV–visible diffuse reflectance spectroscopy, and electron spin resonance analysis. The results showed that the new photocatalysts demonstrated excellent water adsorption properties, high-temperature resistance, and excellent recyclability, which were very suitable for wide application and in line with the concept of green chemistry.